3D printed title

Emily Allen¹, Gabriel King²¹Knoxville Catholic High School ²Sevier County High School

Dr. Kin-ling Sham³, Mariano Del Rosso³, Rakesh Kamath³, Chris Wetteland³, Zane Polmer³, Dr. Hahn Choo³³University of Tennessee, Knoxville

ABSTRACTINTRODUCTIONAdditive manufacturing (AM), AKA 3-D printing, is the process of joining materials to make objects from 3-D model data, usually layer upon layer, as opposed to subtractive manufacturing methodologies.

OBJECTIVES● Determine the different mechanical, thermal, and physical properties of

specific metallically infused PLA filament, iron PLA, copper PLA, and stainless steel PLA, through DSC, TGA, EDXS, and tensile testing.

● Experiment with different technologies and procedures surrounds the field of additive manufacturing and material science

ANALYSIS & RESULTS

CONCLUSION

METHODSDensity Test- Density tests were performed on each of the filaments inorder to compare the found densities with the manufacturer’s previously established densities.

Thermogravimetric Analysis (TGA)-TGA is a technique used tomeasure a sample’s change in weight as heat and time are applied. Differential Scanning Calorimetry (DSC)- DSC is a technique used toobserve a sample’s changes in heat capacity (Cp) as heat is applied. DSC detects, monitors, and graphs phases changes within a sample.Tensile Test- Tensile tests are used to demonstrate and establish themaximum amount of load required to elongate a sample to the breaking point.Energy-Dispersive X-ray Spectroscopy (EDXS)- EDXS is an analytical technique used for the elemental analysts or chemical characterization of a sampleScanning Electron Microscopy (SEM)- SEM captured detailed images ofisolated microscopic regions of the filaments from elemental and chemicalanalysis.

PROBLEM: Analyze the mechanical properties of different metallic PLAs (polylactic acid): copper PLA, iron PLA, and stainless steel PLA against a control neat PLA, as well as the physical and thermal properties.

HYPOTHESIS: If copper PLA, iron PLA, and stainless steel PLA are put through a series of tests and analyses, including a tensile test, TGA, and DSC , then Stainless steel PLA will prove to be the strongest and copper PLA will be capable of the largest length of elongation, and stainless steel PLA will have the smallest maximum elongation.

Fig. 1

Iron PLACopper PLA

Stainless Steel PLA Neat PLA

EDXS tests visually showed the concentration and composition of the different filaments. The images taken from the SEM suggested that there was a substantially larger amount of copper present than in the other metallic PLAs. The qualitative data gathered from this test are validated by the quantitative data from the TGA tests.The quantitative data from TGA proved the amount of metals within each polymer by vaporizing the true PLA, leaving behind the metals. copper PLA contained the most metal, and iron PLA contained the least.

The goal of the DSC test was to confirm the manufacturer’s claim that all samples being observed were, in fact, PLA. The accepted value for the melting point of PLA is between 130-150 degrees Celsius. Alle the samples fell within this range, so it can be deduced that all samples were PLA polymers.

The tests suggest that metallic PLA is, in most circumstances, unnecessary or even harmful in comparison to neat PLA when it comes to applications utilizing strength, ductility, and elongation. More testing is necessary to more deeply understand the capabilities of AM and its materials and their structure-property relationships.

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The tensile test indicates the ultimate tensile strength and maximum elongation at the point of fracture. The data suggests that the neat PLA had the most elastic qualities and also was able to take on the most load of the samples. Copper PLA performed the least efficiently under this test, and stainless steel was average in comparison of the other two. **Due to the extreme similarity between previous tensile test comparisons of iron PLA and stainless steel PLA, iron PLA samples were left out of the tensile test.

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